1. Field of the Invention
The present invention relates in general to computers, and, more particularly, to an apparatus and method of a blade server switch module controlling a blade server storage blade including a Serial-Attached-SCSI (SAS) device via Serial Management Protocol (SMP).
2. Description of the Prior Art
So-called “blade server” computer systems feature a rack-mount enclosure which can hold several “blades.” The blades can include processor blades having a central processing unit and accompanying hardware, and storage blades having media systems such as disk drives arranged in a Redundant Array of Independent Disks (RAID) topology with accompanying controllers, switches and other associated hardware.
In a particular implementation of a blade server system, two separate RAID controller blades are connected to a third drive enclosure blade (DEB). The implementation takes the space of three blade slots in the blade server system's rack mount enclosure. Accompanying each DEB are multiple disk drive cards and controller cards to manage the DEB. The DEB implementation can be functionally equivalent to a Just-A-Bunch-Of-Disks (JBOD) storage array.
A series of external cables can be used to interconnect the DEBs and the RAID controllers. Connectivity is required to daisy chain all the related DEBs together and to also connect the RAID controllers and switches, such as SAS switches. The use of external cables to connect various storage blade components runs contrary to the original and subsequent design philosophies of a blade server computer system, that being to use an internal high-speed fabric which is integrated into the blade server system as a communications and data path. Traditionally, however, the internal high-speed fabric is generic in nature, making the use of the fabric for a specific application difficult.
Computer system design, and in this case design associated with storage devices, is constantly under pressure from the marketplace to provide larger amounts of storage in an increasingly cost-efficient manner. In light of this goal, a design which replaces external cabling with another solution must take cost and efficiency considerations into account.
Thus, a need exists for a system for connecting various storage components of a blade server computer system, such as a RAID controller, which uses the internal fabric of the blade server system rather than employing a network of external cables. In addition, a need exists for a method of configuring and controlling the various interconnected storage components without the use of external cables. The system and method must also take cost considerations into account.